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21.
Summary This study examined the rates of gastric emptying for water and 13 different carbohydrate-containing solutions in seven subjects, using conventional gastric intubation techniques. The rates of gastric emptying for water and a 10% glucose-polymer solution were also measured during 90 min of treadmill running at 75% of each subject's maximum oxygen consumption . At rest, 15% glucose-polymer (P) and fructose (F) solutions emptied more rapidly from the stomach and provided a faster rate of carbohydrate delivery than did a 15% glucose (G) solution (p<0.05). The G solutions showed a constant energy delivery rate of 3.3 kcal · min–1; energy delivery from P and F solutions rose with increasing solution concentrations. The osmolality of the gastric aspirate predicted the rate of gastric emptying for all solutions (p<0.05) but overestimated rates of emptying for 10% and 15% P solutions and underestimated emptying rates for 10% and 15% F solutions. Exercise at 75% decreased the rate of gastric emptying of water but not of 10% P solutions. Thus the different rates of gastric emptying for different carbohydrate-containing solutions were not entirely explained by differences in osmolality. Furthermore, exercise may have different effects on the gastric emptying rates of water and carbohydrate solutions.  相似文献   
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Reciprocal one-way mixed mother-newborn lymphocyte cultures (MMNLC) containing alternatively maternal or newborn responding (R) or stimulating (S) cells were investigated in both directions in primiparae at three different times: a few hours after delivery, and at 4 and at 16 weeks. Cultures were grown in the presence of maternal and pooled control serum prepared from the blood of five to eight unrelated healthy donors. Four weeks after delivery in maternal and in control serum a significant increase in MMNLC reactivity could be observed, which disappeared at 16 weeks when a pronounced decline in MMNLC values in both directions was found. The suppressive effect of maternal serum was more pronounced at delivery, still evident 4 weeks later, and insignificant after 16 weeks. The results of this study suggest that 4 weeks after delivery, maternal sensitization to fetal histocompatibility antigens can be detected in primiparae with MMNLC; and that 16 weeks later, this was no longer detectable with the same test.  相似文献   
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Drugs in nasal preparations, for local use as well as for systemic use, should not interfere with the self-cleaning capacity of the nose, effectuated by the ciliary epithelium. Many drugs and additives, however, have a negative effect on nasal ciliary function. Examples of ciliotoxic agents are lipophilic and mercuric preservatives, local anesthetics, antihistamines, propranolol, and absorption enhancers such as the bile salts. Cholinergic drugs and -adrenergic drugs exert a ciliostimulatory effect. It is the purpose of this review to summarize the present knowledge of ciliotoxicity of drugs and additives and to give recommendations for the use of ciliofriendly drugs in nasal preparations.  相似文献   
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目的:探讨妊娠晚期羊水过少的分娩方式,寻找正确的处理方法,降低围生儿死亡率。方法:对妊娠晚期羊水过少56例作回顾性分析。结果:56例中,30例以羊水过少作为指标行剖宫产,新生儿窒息率为0,19例在临产过程中12例并发胎儿窘迫,7例并发其它高危因素行剖宫产,新生儿窒息率为5.3%,7例经阴道分娩,新生儿均有不同程度窒息。结论:羊水过少一经确诊,应积极引产,估计短时间内不能分娩,及时剖宫产是处理羊水过少较为安全的重要措施。  相似文献   
26.
陈玉环 《黑龙江医学》2001,25(7):488-489
目的 探讨不缝合腹膜剖宫产术式的临床效果。方法 选取剖宫产不缝合腹膜 80例产妇作为观察组 ,与同期分娩按传统方法缝合腹膜产妇 80例作为对照组 ,观察两组术后病率、肠功能恢复及切口愈合情况。结果 观察组术后病 6例 ,对照组 15例 ,两组比较 ,差异有显著性 (P <0 0 5 ) ;观察组术后肛门排气时间为 2 0 5± 5 33h ,对照组为 36 6 7± 6 17h ,两组比较 ,差别有高度统计学意义 (P <0 0 1) ;腹部切口愈合两组无差异。结论 不缝合腹膜剖宫产术式安全、有效、并发症少 ,值得在临床上推广应用。  相似文献   
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ObjectiveTo examine the variability in the cesarean delivery (CD) rates of individual labor and delivery nurses compared with physicians at three attribution time points.Data SourcesMedical record data from nine hospitals in Washington State from January 2016 through September 2018.Study DesignRetrospective, observational cohort design using an aggregated database of birth records.Data Collection/Extraction MethodsChart‐abstracted clinical data from a subset of nulliparous, term, singleton, vertex births attributed at admission, labor management, and delivery to nurses and physicians. Two classification methods were used to categorize nurse‐ and physician‐level CD rates at three attribution time points and the reliability of these methods compared.Principal FindingsThe sample included 12 556 births, 319 nurses, and 126 physicians. Overall, variation in nurse‐level CD rates did not differ significantly across the three attribution time points, and the extent of variation was similar to that observed in physicians. However, agreement between attribution time points varied between 35 percent and 65 percent when classifying individual nurses into the top and bottom deciles. The average reliability of nurse‐level CD rates was 32 percent at admission (IQR 22.0 percent to 38.7 percent), 32.6 percent at labor (IQR 23.1 percent to 40.9 percent), and 29.3 percent (IQR 20.9 percent to 35.8 percent) at delivery. The average reliability of physician‐level CD rates was higher: 54.2 percent (IQR 38.7 percent to 71.4 percent) at admission, 62.5 percent (IQR 49.0 percent to 79.6 percent) at labor management, and 66.1 percent (IQR 53.7 percent to 81.2 percent) at delivery.ConclusionFeedback on nurse‐level CD rates as part of routine clinical quality audits can provide insight into nurse performance in the context of other individual‐level and unit‐level information. To reliably distinguish individual nurse performance, larger sample sizes are needed.  相似文献   
30.
We study the demand-smoothing incentives for private hospitals to perform c-sections. First, we show that a policy change in Chile that increased delivery at private hospitals by reducing the out-of-pocket cost for women with public insurance increased the probability of a c-section by 8.6 percentage points despite private hospitals receiving the same price for a vaginal or cesarean delivery. Second, to understand hospitals’ incentives to perform c-sections, we present a model of hospital decisions about the mode of delivery without price incentives. The model predicts that, because c-sections can be scheduled, a higher c-section rate increases total deliveries, compensating the forgone higher margin of vaginal deliveries. Finally, we provide evidence consistent with the demand-smoothing mechanism: hospitals with higher c-section rates are more likely to reschedule deliveries when they expect a high-demand week.  相似文献   
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